1. Field of the Invention
The present invention relates to a copying machine including a reading unit for reading a document to generate image data, and a recording unit for recording an image on a recording medium based on the image data, and a copying method.
2. Description of the Related Art
In the background art, there is known a multifunctional apparatus having a copying function for making a copy of a document. The multifunctional apparatus has an image reading section such as a CCD (Charge Coupled Device) or a CIS (Contact Image Sensor) for reading while scanning a document to generate image data. The multifunctional apparatus also includes a recording section (such as a laser printer or an ink jet printer) for recording an image on a predetermined recording area of a sheet of recording paper on the basis of the image data. For example, MFC-9800 is a multifunctional apparatus made by Brother Kogyo Kabushiki Kaisha.
When this type multifunctional apparatus is applied to an A4 size, the maximum document size is an A4 size (document width: 210 mm) or a letter size (document width: 216 mm). As shown in FIG. 9A, only an area corresponding to the recording area of recording paper can be read from a document by the image reading section at the time of copying in order to reduce the data amount of image data. The width of the recording area (the horizontally recordable width in FIG. 9A) is 206 mm. Left and right margins (2 mm-wide margins in the A4 size or 5 mm-wide margins in the letter size) of the document are not read by the image reading section because images on the left and right margins cannot be recorded on a sheet of recording paper.
Also, top and bottom margins of the document are not read by the image reading section, either.
This is for the following reason. When the multifunctional apparatus is used as a facsimile machine or as a scanner, it is necessary to read all the designated area. However, when the multifunctional apparatus is used as a copying machine, it is wasteful to read the other area than the recordable area because the recordable area is known from the start. Accordingly, when the multifunctional apparatus is used as a copying machine, only the recordable area is read in order to improve both memory efficiency and processing speed.
When the multifunctional apparatus according to the related art is used as a copying machine, the image reading section does not read peripheral margins of the document as described above. Therefore, image data does not contain an image recorded on the peripheral margins. For this reason, as shown in FIG. 9B, images recorded on the peripheral margins of the document cannot be recorded on the sheet of recording paper when image data are reduced and recorded. There is a problem that a wide blank portion is produced in a peripheral portion of the recording area because image data are missing in the peripheral portion of the recording area.
Moreover, when the image reading section reads the document in the condition that the document is skewing, a certain portion that is supposed to be present in the area read by the image reading section originally (when the document is not skewing) may be out of the readable area. As a result, the certain portion cannot be recorded on the sheet of recording paper and is missing. There is a problem that copying loss increases.